org.springframework.cloud.stream.metrics.config.MetricJsonSerializer.java Source code

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Here is the source code for org.springframework.cloud.stream.metrics.config.MetricJsonSerializer.java

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/*
 * Copyright 2017 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.cloud.stream.metrics.config;

import java.io.IOException;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.TimeZone;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.LinkedBlockingQueue;

import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonDeserializer;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.SerializerProvider;

import org.springframework.boot.actuate.metrics.Metric;
import org.springframework.boot.jackson.JsonComponent;

/**
 * @author Vinicius Carvalho
 * @author Oleg Zhurakousky
 */
@JsonComponent
public class MetricJsonSerializer {

    private static final BlockingQueue<DateFormat> formatters = new LinkedBlockingQueue<DateFormat>();

    private static DateFormat defaultDateFormat() {
        DateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSX");
        df.setTimeZone(TimeZone.getTimeZone("GMT"));
        return df;
    }

    public static class Serializer extends JsonSerializer<Metric<?>> {

        @Override
        public void serialize(Metric<?> metric, JsonGenerator json, SerializerProvider serializerProvider)
                throws IOException {
            json.writeStartObject();
            json.writeStringField("name", metric.getName());
            json.writeNumberField("value", metric.getValue().doubleValue());
            DateFormat df = formatters.poll();
            if (df == null) {
                df = defaultDateFormat();
            }
            try {
                json.writeStringField("timestamp", df.format(metric.getTimestamp()));
                json.writeEndObject();
            } finally {
                formatters.offer(df);
            }
        }
    }

    public static class Deserializer extends JsonDeserializer<Metric<?>> {

        @Override
        public Metric<?> deserialize(JsonParser p, DeserializationContext ctxt)
                throws IOException, JsonProcessingException {
            JsonNode node = p.getCodec().readTree(p);
            String name = node.get("name").asText();
            Number value = node.get("value").asDouble();
            Date timestamp = null;
            DateFormat df = formatters.poll();
            if (df == null) {
                df = defaultDateFormat();
            }
            try {
                timestamp = df.parse(node.get("timestamp").asText());
            } catch (ParseException e) {
                // ignore timestamp parsing errors
            } finally {
                formatters.offer(df);
            }
            Metric<Number> metric = new Metric<>(name, value, timestamp);
            return metric;
        }

    }
}